The present invention relates to thermoplastic dicyclopentadiene ring-opening polymers and a method for producing the same, and, more particularly, to thermoplastic dicyclopentadiene ring-opening polymers excellent in hydrogenation efficiency after ring-opening polymerization and capable of providing hydrogenation products excellent in mechanical strength; hydrogenation products thereof; and a method for producing dicyclopentadiene ring-opening polymers which is excellent in conversion and can diminish the amount of catalysts used.
Furthermore, the present invention relates to wire coating materials comprising cyclic olefin polymers, and, more particularly, to wire coating materials excellent in flexing resistance and flexibility, and wires comprising a conductor around which said wire coating material is provided, such as high-voltage power cables and high frequency cables.
Moreover, the present invention relates to plate lenses formed of thermoplastic resins having an alicyclic structure, and, more particularly, to plate lenses made of thermoplastic hydrocarbon resins excellent in mechanical strength, impact strength and transparency, and a method for producing the same.
In addition, the present invention relates to agricultural films excellent in mechanical strength, elongation, chemical resistance, weathering resistance and light transmission.
Further, the present invention relates to composite films excellent in mechanical strength and chemical resistance, and, besides, in gas barrier properties and water vapor barrier properties, and a method for producing the same.
Moreover, the present invention relates to food packaging films excellent in mechanical strength, elongation, oil resistance, transparency and water vapor barrier properties.
Furthermore, the present invention relates to impact-resistant plate members excellent in mechanical strength, elongation, chemical resistance, weathering resistance and light transmission, and, more particularly, to impact-resistant plate members excellent in transparency and suitable for outdoor use.
Thermoplastic dicyclopentadiene ring-opening polymers and hydrogenation products thereof are excellent in balancing of various properties such as heat resistance, transparency, water resistance (water absorption resistance, moisture resistance), chemical resistance, solvent resistance, dielectric characteristics (low dielectric constant, low dielectric loss), low birefringence, and stiffness. Therefore, they are used in a wide variety of fields, for example, as optical materials, medical equipment, electrical insulating materials, and electronic part processing materials which are made by various molding methods such as injection molding, extrusion molding, compression molding and solvent-casting.
Thermoplastic dicyclopentadiene ring-opening polymers can be obtained by subjecting dicyclopentadiene (hereinafter referred to as xe2x80x9cDCPxe2x80x9d) or derivatives thereof (hereinafter referred to as xe2x80x9cDCP monomersxe2x80x9d including both the DCP and derivatives thereof) in a suitable solvent in the presence of a ring-opening polymerization catalyst such as a metathesis catalyst. Hydrogenation products thereof can be obtained by hydrogenating carbon-carbon unsaturated bonds (such as carbon-carbon double bonds in main chains and polycyclic rings) in thermoplastic DCP ring-opening polymers. Hydrogenation of thermoplastic DCP ring-opening polymers to saturate the carbon-carbon unsaturated bonds results in improvement of various properties such as heat resistance, weathering resistance, light resistance, solvent resistance, chemical resistance and water resistance. Thermoplastic DCP ring-opening polymers can also be obtained by subjecting a DCP monomer and other ring-opening copolymerizable norbornene monomer to ring-opening copolymerization in the presence of a ring-opening polymerization catalyst. In this case, heat resistance, mechanical properties, etc. can be improved by selecting kind and copolymerization ratio of the other norbornene monomers used as comonomers. The resulting ring-opening copolymers can be hydrogenated, if necessary.
In general, DCP ring-opening polymers can be roughly classified into thermoplastic DCP ring-opening polymers and curing type DCP ring-opening polymers. The curing type DCP ring-opening polymers are obtained by bulk ring-opening polymerization reaction using polymerization catalysts of relatively high activity, such as tungsten-based ring-opening polymerization catalysts or molybdenum-based ring-opening polymerization catalysts. The curing type DCP ring-opening polymers are used for making molded products by reactive injection molding (RIM) method using DCP monomers (e.g., JP-A-58-127728, JP-A-58-129013, JP-A-4-226114, JP-A-6-145247, etc.). In the case of producing curing type DCP ring-opening polymers, generally, a reaction mixture containing a DCP monomer and a ring-opening polymerization catalyst is injected into a mold to carry out bulk ring-opening polymerization, and, hence, they can be obtained as molded products of a given shape after completion of the polymerization reaction. Thus, as for curing type DCP ring-opening polymers, since molded products can be obtained without employing melt molding methods (e.g., injection molding, extrusion molding and compression molding), no problems are caused even if the ring-opening polymerization is carried out under such conditions that there takes place an abrupt reaction at the time of the bulk ring-opening polymerization or there take place an intermolecular and/or intramolecular crosslinking reactions caused by the carbon-carbon double bond in the main chain or side chain produced by the ring-opening reaction. Therefore, in the production of heat-curing type DCP ring-opening polymers, ring-opening polymerization catalysts of high activity are selected and used for shortening the reaction time in the mold, whereby crosslinked cured polymers are obtained.
On the other hand, titanium-based ring-opening polymerization catalysts have been mainly used for the production of thermoplastic DCP ring-opening polymers (e.g., JP-B-58-43412 and JP-A-7-220230). However, in the conventional production methods using titanium-based ring-opening polymerization catalysts, the resulting polymers have a problem in solubility, and if aromatic hydrocarbon solvents such as toluene high in dissolvability for polymers are used, the solvents are also hydrogenated at the time of hydrogenation reaction and thus efficiency of the hydrogenation reaction is deteriorated. Furthermore, according to the above methods, since ring-opening polymerization activity is low, there are problems that conversion of polymerization does not increase, ring-opening polymerization catalysts must be used in a large amount, wastes of catalyst residues are produced in large quantity, and productivity is low.
JP-A-63-218727 and JP-A-7-41549 disclose methods for ring-opening polymerization of DCP monomers using tungsten-based ring-opening polymerization catalysts. These methods have the merits that conversion is high and the ring-opening polymerization catalysts can be used in a small amount, but have the following problems, namely, a part of carbon-carbon double bonds are crosslinked to result in gelation at the time of the ring-opening polymerization to make it difficult to separate the resulting polymer from the reaction mixture and dry it; the subsequent hydrogenation reaction does not efficiently proceed owing to the high viscosity of the reaction mixture; and molded products obtained from the resulting ring-opening polymers or hydrogenation products thereof are inferior in mechanical strength. Further problem is that when the hydrogenation products are extrusion molded or injection molded, the pellets adhere to the lower part of the hopper (bridging in the hopper) to cause clogging of the hopper.
As mentioned above, hitherto, there have been known no thermoplastic DCP ring-opening polymers which are high in productivity in polymerization, hardly leave wastes of catalyst residues, are high in activity of the subsequent hydrogenation reaction, and are excellent in moldability when used as molding materials after hydrogenation reaction, and no methods for producing the same have been known.
An object of the present invention is to provide thermoplastic DCP ring-opening polymers which are high in productivity in polymerization, hardly leave wastes of catalyst residues, are high in activity of the subsequent hydrogenation reaction, and are excellent in moldability when used as molding materials after hydrogenation reaction, and a method for producing the same.
Another object of the present invention is to provide materials having well-balanced excellent flexing resistance, flexibility and strength characteristics sufficient as wire coating materials with maintaining excellent dielectric characteristics, water tree resistance and endurance possessed by amorphous polyolefins.
Further object of the present invention is to provide plate lenses made of thermoplastic resins excellent in transparency, mechanical strength, impact strength and molding processability and small in change due to moisture absorption, and a method for producing the same.
Further another object of the present invention is to provide agricultural films excellent in mechanical strength, elongation, chemical resistance, weathering resistance and light transmission, and comprising resins containing no halogen atoms such as chlorine atom.
Still another object of the present invention is to provide composite films excellent in mechanical strength and chemical resistance, and, besides, in gas barrier properties and water vapor barrier properties, and a method for producing the same.
Further object of the present invention is to provide food packaging films excellent in mechanical strength, elongation, oil resistance, transparency and water vapor barrier properties.
Still further object the present invention is to provide impact-resistant plate members excellent in mechanical strength, elongation, chemical resistance, weathering resistance and light transmission.
As a result of research conducted by the inventors, it has been found that according to the conventional solution polymerization of DCP monomers using tungsten-based ring-opening polymerization catalysts, gelation is apt to occur at the time of ring-opening polymerization and, besides, low-molecular weight components (namely, oligomers) of 2, 000 or less in molecular weight are apt to be produced, and, hence, the resulting thermoplastic DCP ring-opening polymers are deteriorated in mechanical strength.
As a result of further research conducted by the inventors, it has been found that in a method for the production of thermoplastic dicyclopentadiene ring-opening polymers by ring-opening polymerization of dicyclopentadiene monomers in the presence of ring-opening polymerization catalysts such as tungsten-based ring-opening polymerization catalysts, production of gel and low-molecular weight components can be considerably inhibited by allowing at least one compound selected from the group consisting of a nitrile, a ketone, an ether and an ester to be present as a reaction regulator. According to the method of the present invention, since not only the production of the crosslinked polymer component, but also the production of low-molecular weight component can be effectively inhibited, thermoplastic DCP ring-opening polymers excellent in productivity, moldability, mechanical strength, and hydrogenation efficiency can be obtained.
In the thermoplastic DCP ring-opening polymers of the present invention, the proportion of repeating units in which polycyclic rings are bonded in cis-position relative to the carbon-carbon double bond of the main chain is 50 mol % or more and the content of a low-molecular weight component of 2,000 or less in molecular weight is low, namely, 10% by weight or less. The thermoplastic DCP ring-opening polymers of the present invention are soluble in saturated hydrocarbon solvents and, hence, can be efficiently hydrogenated and hydrogenation products excellent in mechanical strength can be obtained.
It has been further found that by using the hydrogenation products of the present invention, there can be obtained wire coating materials excellent in elongation, impact strength, etc; plate lenses which are hardly broken even when thinned in wall and thus can be reduced in weight and be made large-sized, excellent in tenacity and hence can be adapted to curved picture surface, can be highly miniaturized, and, besides, are small in deterioration of optical performance; agricultural films excellent in all of the characteristics of mechanical strength, elongation, chemical resistance, weathering resistance and light transmission; composite films excellent in mechanical strength and chemical resistance, and, besides, in gas barrier properties and water vapor barrier properties; food packaging films excellent in mechanical strength, elongation, oil resistance, transparency and water vapor barrier properties; and impact-resistant plate members excellent in all of the characteristics of mechanical strength, elongation, chemical resistance, weathering resistance and light transmission.
The present invention has been accomplished based on these findings. Thus, according to the present invention, the following are provided.
That is, the present invention is a thermoplastic dicyclopentadiene ring-opening polymer obtained by ring-opening polymerization of a monomer component containing a dicyclopentadiene monomer, characterized in that polycyclic rings which are repeating units of the polymer are bonded in cis-position relative to the carbon-carbon double bond in the main chain in a proportion of 50 mol % or more of the total repeating units and the content of a low-molecular weight component of 2,000 or less in molecular weight is 10% by weight or less based on the total polymer components.
Furthermore, the present invention is a method for producing a thermoplastic dicyclopentadiene ring-opening polymer by ring-opening polymerization of a monomer component containing a dicyclopentadiene monomer in the presence of a ring-opening polymerization catalyst, characterized in that the ring-opening polymerization is carried out in the presence of at least one compound selected from the group consisting of a nitrile, a ketone, an ether and an ester as a reaction regulator.
Furthermore, the present invention relates to a hydrogenation product obtained by hydrogenating the carbon-carbon unsaturated bond of the above thermoplastic dicyclopentadiene ring-opening polymer.
Furthermore, the present invention relates to a wire coating material containing the hydrogenation product.
Furthermore, the present invention relates to a plate lens containing the hydrogenation product.
Furthermore, the present invention relates to an agricultural film containing the hydrogenation product.
Furthermore, the present invention relates to a composite film containing at least one layer of film (A) comprising the above hydrogenation product and at least one layer of film (B) comprising a polyvinyl alcohol-based polymer.
Furthermore, the present invention relates to a food packaging film containing the hydrogenation product.
Furthermore, the present invention relates to an impact resistant plate member containing the hydrogenation product.